Add error checking

Author: perry-ca

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -9498,6 +9498,8 @@ def warn_redefine_extname_not_applied : Warning<
   "#pragma redefine_extname is applicable to external C declarations only; "
   "not applied to %select{function|variable}0 %1">,
   InGroup<Pragmas>;
+def err_cannot_be_exported : Error<
+  "cannot be '_Export` qualified">;
 } // End of general sema category.
 
 // inline asm.

clang/lib/Parse/ParseStmt.cpp

@@ -538,6 +538,7 @@ StmtResult Parser::ParseStatementOrDeclarationAfterAttributes(
   case tok::annot_pragma_attribute:
     HandlePragmaAttribute();
     return StmtEmpty();
+
   case tok::annot_pragma_export:
     ProhibitAttributes(CXX11Attrs);
     ProhibitAttributes(GNUAttrs);

clang/lib/Sema/SemaDecl.cpp

@@ -6503,10 +6503,10 @@ NamedDecl *Sema::HandleDeclarator(Scope *S, Declarator &D,
           existingAttr->getVisibility();
       if (existingValue != VisibilityAttr::Default)
         Diag(D.getExportLoc(), diag::err_mismatched_visibility);
-    } else {
+    } else
+      // Add VisibilityAttr::Default since the default could be hidden, etc
       New->addAttr(
           VisibilityAttr::CreateImplicit(Context, VisibilityAttr::Default));
-    }
   }
 
   // If this has an identifier and is not a function template specialization,
@@ -6746,6 +6746,9 @@ Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC,
     return nullptr;
   }
 
+  if (D.IsExport())
+    Diag(D.getName().StartLocation, diag::err_cannot_be_exported);
+
   TypedefDecl *NewTD = ParseTypedefDecl(S, D, TInfo->getType(), TInfo);
   if (!NewTD) return nullptr;
 
@@ -8208,6 +8211,9 @@ NamedDecl *Sema::ActOnVariableDeclarator(
 
   ProcessPragmaWeak(S, NewVD);
 
+  if (D.IsExport() && !NewVD->hasExternalFormalLinkage())
+    Diag(D.getIdentifierLoc(), diag::err_cannot_be_exported);
+
   // If this is the first declaration of an extern C variable, update
   // the map of such variables.
   if (NewVD->isFirstDecl() && !NewVD->isInvalidDecl() &&
@@ -10851,6 +10857,10 @@ Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
   }
 
   ProcessPragmaWeak(S, NewFD);
+
+  if (D.IsExport() && !NewFD->hasExternalFormalLinkage())
+    Diag(D.getIdentifierLoc(), diag::err_cannot_be_exported);
+
   checkAttributesAfterMerging(*this, *NewFD);
 
   AddKnownFunctionAttributes(NewFD);
@@ -15343,6 +15353,9 @@ Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D,
   if (getLangOpts().OpenCL)
     deduceOpenCLAddressSpace(New);
 
+  if (D.IsExport())
+    Diag(D.getIdentifierLoc(), diag::err_cannot_be_exported);
+
   return New;
 }
 
@@ -18705,6 +18718,9 @@ FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record,
   } else
     Record->addDecl(NewFD);
 
+  if (D.IsExport())
+    Diag(D.getIdentifierLoc(), diag::err_cannot_be_exported);
+
   return NewFD;
 }
 

clang/test/Sema/attr-export-failing.cpp

@@ -13,15 +13,3 @@ int v0;
 static int s0; // expected-warning{{#pragma export is applicable to symbols with external linkage only; not applied to 's0'}}
 #pragma export(sf0)
 #pragma export(s0)
-
-typedef int _Export ty;
-ty x;
-int f(int _Export x);
-static int _Export s;
-struct S {
-  int _Export nonstaticdatamember;
-};
-void g() {
-  int _Export automatic;
-}
-

clang/test/Sema/zos-export.c

@@ -1,12 +1,25 @@
 // RUN: %clang_cc1 -triple s390x-ibm-zos %s -fsyntax-only -verify
 
-typedef int _Export ty;
+typedef int _Export ty; //expected-error {{cannot be '_Export` qualified}}
 ty x;
-int f(int _Export x);
-static int _Export s;
+int f(int _Export argument); //expected-error {{cannot be '_Export` qualified}}
+static int _Export file_scope_static; //expected-error {{cannot be '_Export` qualified}}
 struct S {
-  int _Export nonstaticdatamember;
+  int _Export nonstaticdatamember; //expected-error {{cannot be '_Export` qualified}}
 };
 void g() {
-  int _Export automatic;
+  int _Export automatic; //expected-error {{cannot be '_Export` qualified}}
 }
+
+static void _Export static_func() { //expected-error {{cannot be '_Export` qualified}}
+}
+
+void _Export h() {
+  static_func();
+}
+
+void j() {
+  static int _Export sl = 0; //expected-error {{cannot be '_Export` qualified}}
+}
+
+int _Export file_scope;

clang/test/Sema/zos-export.cpp

@@ -0,0 +1,44 @@
+// RUN: %clang_cc1 -triple s390x-ibm-zos %s -fsyntax-only -verify
+
+typedef int _Export ty; //expected-error {{cannot be '_Export` qualified}}
+ty typedef_var;
+int f(int _Export argument); //expected-error {{cannot be '_Export` qualified}}
+static int _Export file_scope_static; //expected-error {{cannot be '_Export` qualified}}
+struct S {
+  int _Export nonstaticdatamember; //expected-error {{cannot be '_Export` qualified}}
+};
+void g() {
+  int _Export automatic; //expected-error {{cannot be '_Export` qualified}}
+}
+
+static void _Export static_func() { //expected-error {{cannot be '_Export` qualified}}
+}
+
+void _Export h() {
+  static_func();
+}
+
+void j() {
+  static int _Export sl = 0; //expected-error {{cannot be '_Export` qualified}}
+}
+
+int _Export file_scope;
+
+struct _Export SE {
+};
+
+struct ST {
+  void _Export f();
+  virtual void _Export v_();
+  static int _Export i;
+};
+
+namespace {
+  int _Export anon_var; //expected-error {{cannot be '_Export` qualified}}
+  extern "C" int _Export anon_C_var;
+  void _Export anon_f() {} //expected-error {{cannot be '_Export` qualified}}
+  extern "C" void _Export anon_C_f() {}
+  struct anon_S {
+    static int _Export anon_static_data_member; //expected-error {{cannot be '_Export` qualified}}
+  };
+}